Passivated niobium cavities
- Yorktown, VA
- Lagga Arby, SE
- Newport News, VA
A niobium cavity exhibiting high quality factors at high gradients is provided by treating a niobium cavity through a process comprising: 1) removing surface oxides by plasma etching or a similar process; 2) removing hydrogen or other gases absorbed in the bulk niobium by high temperature treatment of the cavity under ultra high vacuum to achieve hydrogen outgassing; and 3) assuring the long term chemical stability of the niobium cavity by applying a passivating layer of a superconducting material having a superconducting transition temperature higher than niobium thereby reducing losses from electron (cooper pair) scattering in the near surface region of the interior of the niobium cavity. According to a preferred embodiment, the passivating layer comprises niobium nitride (NbN) applied by reactive sputtering.
- Research Organization:
- Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-84ER40150
- Assignee:
- Jefferson Science Associates LLC (Newport News, VA)
- Patent Number(s):
- 7,151,347
- Application Number:
- 11/168,198
- OSTI ID:
- 982424
- Country of Publication:
- United States
- Language:
- English
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